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Cusps and $q$-expansion principles for modular curves at infinite level. (arXiv:2002.02488v1 [math.NT]) http://arxiv.org/abs/2002.02488
Cusps and $q$-expansion principles for modular curves at infinite level. (arXiv:2002.02488v1 [math.NT]) http://arxiv.org/abs/2002.02488